1 /**
2  * Copyright (c) 2023 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *   http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include <signal.h>
17 #include <stdio.h>
18 #include <sys/wait.h>
19 #include "gwp_asan_test.h"
20 #include "test.h"
21 
buffer_underflow_handlernull22 void buffer_underflow_handler()
23 {
24     find_and_check_file(GWP_ASAN_LOG_DIR, GWP_ASAN_LOG_TAG, "Buffer Underflow");
25     clear_log(GWP_ASAN_LOG_DIR, GWP_ASAN_LOG_TAG);
26     cancel_gwp_asan_environment(true);
27     _exit(0);
28 }
29 
install_sigv_handlernull30 static void install_sigv_handler()
31 {
32     struct sigaction sigv = {
33         .sa_handler = buffer_underflow_handler,
34         .sa_flags = 0,
35     };
36     sigaction(SIGSEGV, &sigv, NULL);
37 }
38 
buffer_underflow_testnull39 void buffer_underflow_test()
40 {
41     config_gwp_asan_environment(true);
42     clear_log(GWP_ASAN_LOG_DIR, GWP_ASAN_LOG_TAG);
43     install_sigv_handler();
44 
45     char *ptr = (char *)malloc(sysconf(_SC_PAGE_SIZE));
46     if (!ptr) {
47         t_error("malloc failed.");
48         return;
49     }
50     if (!libc_gwp_asan_ptr_is_mine(ptr)) {
51         t_error("FAIL enter gwp_asan malloc failed!\n");
52         return;
53     }
54     char c = *(ptr - 1);
55     printf("c:%c", c);
56 }
57 
58 /*
59  *
60  *|--guard area--|--malloc area--|--guard area--|
61  *              ^
62  */
mainnull63 int main()
64 {
65     pid_t pid = fork();
66     if (pid < 0) {
67         t_error("FAIL fork failed.");
68     } else if (pid == 0) { // child process
69         buffer_underflow_test();
70     } else { // parent process
71         int status;
72         if (waitpid(pid, &status, 0) != pid) {
73             t_error("gwp_asan_buffer_underflow_test waitpid failed.");
74         }
75 
76         if (WIFEXITED(status) && WEXITSTATUS(status) != 0) {
77             t_error("gwp_asan_buffer_underflow_test failed.");
78         }
79 
80         cancel_gwp_asan_environment(true);
81     }
82 
83     return t_status;
84 }